1. Field of the Invention
The present invention relates to a hydrofoil, and more particularly to a hydrofoil which can fly in water stably via a float structure.
2. Description of the Prior Art
Hydrofoil is a high-speed boat that is provided with a frame at a bottom for assembling wings. When the speed of the boat increases, the wings can provide buoyant force to lift the boat out of the water, forming the so-called hydrofoil flight or navigation, thus largely reducing drag in the water and increasing the navigation speed.
Referring to FIGS. 1 and 2, a conventional hydrofoil 10 comprises a body 11, both sides of the body 11 are provided with the same number of wings 12 having propellers 121 at a rear edge thereof, and at a bottom of the body 11 is provided a float device 13 having a plurality of elongated first floats 131. Both ends of each first float 131 are provided with propellers 135, and a sheet-shaped connecting portion 132 is extended from the first float 131 to connect the first float 131 to the bottom of the body 11. The float device 13 is further provided with two second floats 133 located at both sides of the body 11 and adjacent to the bottom of the body 11, and the second floats 133 are connected to the body 11 via two bent connecting portions 134. Therefore, as shown in FIG. 2, when the hydrofoil 10 stops moving, the first floats 131 are submerged under the surface of the water completely, and the second floats 133 are floated on the surface of the water, so as to make the body 11 float on the surface of the water. When the hydrofoil 10 flies on the surface of the water, the connecting portions 132 of the first floats 131 and the second floats 133 will be lifted completely from the surface of the water to make the hydrofoil 10 fly stably above the water.
However, since the floats of the float device 13 of the hydrofoil 10 are elongated and are extended from the body 11, no matter the hydrofoil 10 is moving or not, the waves coming from both sides of the body 11 will impact on the first floats 131 or the second floats 133, causing instability of the body 11. Especially, as compared with the cylindrical floats which can shunt the waves slightly, when the hydrofoil 10 moves fast, the water waves coming from both sides of the body 11 will impact on the connecting portions 132 of the first floats 131 to further cause instability of the body 11. Therefore, such a conventional hydrofoil 10 is unstable and uncomfortable.
Therefore, maintaining the hydrofoil 10 always in the horizontal position is extremely difficult. The floats have to be connected to the body 11 via the connecting portions 132, then with the aid of the wings 12, the hydrofoil 10 is able to keep staying in the horizontal state. However, when the wings encounter turbulent flow, the first floats 13 will move up and down along with the hydrofoil 10, the periphery of the first floats 131 changes from the state of being stressed uniformly to a surface contact in a single direction, which is likely to cause expected path change after the floats are struck by high speed water flow. More particularly, the reaction force of water is much bigger than that of airflow. Hence, the faster the speed or the larger the angle changed, the resultant impact will become more obvious, the hydrofoil 10 will jump up and down in a rapid manner, making the sailing very unstable.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.